1. Field of the Invention
The present invention relates to the mechanical arts. In particular, the present invention relates to collision safety devices for minimizing property damage and personal injury in vehicular collisions with roadside posts.
2. Description of Related Art
Roadside posts are used for supporting electric and communications utility wires, signage, traffic signals, fencing and for other purposes. A vehicle leaving the roadway risks striking one of these posts.
Collisions with roadside posts often cause severe damage to the post and its foundation. In addition, the vehicle involved in the collision often experiences severe damage. Repair costs for the roadside post and for the vehicle involved in the collision are significant. Moreover, injuries to vehicle occupants may result.
In a vehicular collision with a conventional roadside post, a relatively large fraction of the vehicle's kinetic energy is absorbed when the post and the vehicle are deformed. Current roadside post designs feature a rigid attachment between the post and its foundation. When a vehicle collides with the post, the post resists being separated from its foundation, while the colliding vehicle expends its kinetic energy in an attempt to overcome that resistance. During this process, unnecessarily large deformations of both the post and the vehicle occur.
Consequently, there has been a long felt need of a system that reduces the energy exchanged between the post and the vehicle during a collision to reduce post and vehicle damage and the related injuries to vehicle occupants.